CI(build-and-test): run benchmarks after deploy job (#10791)

## Problem

`benchmarks` is a long-running and non-blocking job. If, on Staging, a
deploy-blocking job fails, restarting it requires cancelling any running
`benchmarks` jobs, which is a waste of CI resources and requires a
couple of extra clicks for a human to do.

Ref: https://neondb.slack.com/archives/C059ZC138NR/p1739292995400899

## Summary of changes
- Run `benchmarks` after `deploy` job
- Handle `benchmarks` run in PRs with `run-benchmarks` label but without
`deploy` job.

.github/workflows/build_and_test.yml

@@ -263,8 +263,9 @@ jobs:
           echo "json=$(jq --compact-output '.' /tmp/benchmark_durations.json)" >> $GITHUB_OUTPUT
 
   benchmarks:
-    if: github.ref_name == 'main' || contains(github.event.pull_request.labels.*.name, 'run-benchmarks')
-    needs: [ check-permissions, build-and-test-locally, build-build-tools-image, get-benchmarks-durations ]
+    # `!failure() && !cancelled()` is required because the workflow depends on the job that can be skipped: `deploy` in PRs
+    if: github.ref_name == 'main' || (contains(github.event.pull_request.labels.*.name, 'run-benchmarks') && !failure() && !cancelled())
+    needs: [ check-permissions, build-build-tools-image, get-benchmarks-durations, deploy ]
     permissions:
       id-token: write # aws-actions/configure-aws-credentials
       statuses: write